The legal threats suggest the election of an oil-friendly, Republican-dominated Congress hasn't put recent pipeline battles to rest.
One activist fighting the Keystone XL project in Nebraska says landowners will sue should President Barack Obama sign any pro-Keystone bill passed by the new Congress.
Jane Kleeb says the grounds for such a suit would be constitutional, and revolve around whether Congress actually has the power to pass legislation on such cross-border infrastructure.
She compares it to the case currently before the Nebraska courts, which argues that the process to approve the route in that state was unconstitutional.
There's also a new lawsuit against another pipeline from Canada — this one in a Minnesota court against Enbridge Inc.'s plan to expand its existing Alberta Clipper network.
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